Effects of Facet Orientation on Relative Stability between Zinc Blende and Wurtzite Structures in Group III–V Nanowires

Abstract

The relative stability between the wurtzite and zinc blende structures in InP, GaP, and GaAs nanowires with {111}/{1100} facets and those with {110}/{1120} facets is systematically investigated using our empirical interatomic potential calculations in conjunction with first-principles calculations. Moreover, we discuss chemical trends in the structural stability of InP, GaP, and GaAs nanowires. Our calculations clarify that the wurtzite structure is stabilized over the entire diameter range for nanowires with {111}/{1100} facets. In contrast, for nanowires consisting of {110}/{1120} facets, the crystal structure of nanowires depends on the nanowire diameter and the ionicity of semiconductors. This is because the surface energy difference between the {111} and {1100} surfaces is large compared with that between the {110} and {1120} surfaces. The calculated results imply that the stability of nanowire side facets is an important factor determining the crystal structure.